Indolothiopyrones

Abstract

This invention relates to novel indolothiopyrones having the formula: ##SPC1## Wherein R 1 is hydrogen, lower alkyl or aryl; R 2 is hydrogen or halogen; and R 7 is hydrogen, lower alkyl, lower alkenyl, lower alkynyl, nitro-substituted-aryl, or ω-substituted lower alkyl wherein the substituent is: ##EQU1## --COOH, or ##EQU2## wherein R 4 and R 5 each represent hydrogen, lower alkyl, or together with the nitrogen atom, form a heterocyclic ring; and R 6 is lower alkoxy or amino, and novel intermediates used in their preparation. The indolothiopyrones are prepared by reacting a 3-mercaptoindole with sodium propiolate or a substituted sodium propiolate followed by acidification to obtain an intermediate acid; the intermediate acid cyclizes in the presence of an acid catalyst to obtain the indolothiopyrone structure which may be additionally subjected to halogenation, alkylation or hydrolysis to obtain derivatives having the various substituent groups disclosed. The compounds of this invention are useful in the treatment of angina pectoris and conditions benefiting from the depression of the central nervous system.

I claim: 
     
       1. A compound of the formula IX: ##SPC32## wherein R 1  is hydrogen, 1 to 4 carbon lower alkyl or phenyl; R 2  is hydrogen or halogen; and R 7  is hydrogen, 1 to 4 carbon lower alkyl, 3 to 4 carbon lower alkenyl, 3 to 4 carbon lower alkynyl, nitro-substituted-phenyl, or ω -substituted 1 to 4 carbon lower alkyl wherein the substituent is: ##EQU12## --COOH, or ##EQU13## wherein R 4  and R 5  each represent hydrogen or 1 to 4 carbon lower alkyl; and R 6  is 1 to 4 carbon lower alkoxy or amino.   
     
     
       2. A compound according to claim 1 wherein R 1  is hydrogen, methyl, or phenyl; R 2  is hydrogen, chloro or bromo; and R 7  is hydrogen, methyl, ethyl, propyl, isopropyl, allyl, propargyl, o-nitrophenyl, (dimethylamino)propyl, carboxymethyl, (ethoxycarbonyl)methyl. 
     
     
       3. The compound according to claim 2 which is thiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       4. The compound according to claim 2 which is 2-methylthiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       5. The compound according to claim 2 which is 2-phenylthiopyrano[3,2-b]indol-4(5H)-one 
     
     
       6. The compound according to claim 2 which is 5-methylthiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       7. The compound according to claim 2 which is 5-ethylthiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       8. The compound according to claim 2 which is 5-allylthiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       9. The compound according to claim 2 which is 5-isopropylthiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       10. The compound according to claim 2 which is 5-(o-nitrophenyl)thiopyrano[3,2-b]indol-4-(5H)-one. 
     
     
       11. The compound according to claim 2 which is ethyl 4,5-dihydro-4-oxothiopyrano[3,2-b]indol-5-acetate. 
     
     
       12. The compound according to claim 2 which is 5-propargylthiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       13. The compound according to claim 2 which is 5-[3(dimethylamino)propyl]thiopyrano[3,2-b]indol-4(5H)-one hydrochloride. 
     
     
       14. The compound according to claim 2 which is 4,5-dihydro-4-oxothiopyrano[3,2-b]indole-5-acetic acid. 
     
     
       15. The compound according to claim 2 which is 8-bromothiopyrano[3,2-b]indol-4(5H)-one. 
     
     
       16. The compound according to claim 2 which is 8-bromo-5-methylthiopyrano[3,2-b]indol-4-(5H)-one.